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Scintillation Detectors
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
This is the aluminium oxide version of the oxyorthosilicates; they have in general higher densities, higher indices of refraction, shorter decay times, shorter peak emission wavelengths, and lower light yields than their orthosilicate cousins. YAP:Ce (YAlO3:Ce) is famous for being one of very few scintillation materials showing almost perfect energy linearity (see below). With an energy resolution around 4 per cent it is an interesting alternative to NaI(Tl) in applications not requiring high density or zeff materials, for example, small dimension imaging detectors using 140 keV photons. The YAP:Ce is neither fragile nor hygroscopic and can relatively easily be machined in suitable sizes for instance to be used in array-detectors for positions sensing or as charged particle detectors [47]. It is also one of the fastest oxide scintillators. It has been observed that the nonproportionality of YAP is correlated to the Ce-concentration in the material [48], higher Ce-concentrations correlated both with improved nonproportionality and faster decay time.
Thermoluminescence Dosimetry
Published in Arash Darafsheh, Radiation Therapy Dosimetry: A Practical Handbook, 2021
Many more materials exist and the table has been provided more to illustrate certain features than to provide an exhaustive summary of materials. Another important material is Beryllium Oxide (BeO) [41] because of its tissue equivalence and the fact that like Aluminum Oxide it is also useful for OSL dosimetry which extends usability (and scientific interest).
Inhalation Toxicity of Metal Particles and Vapors
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
The use of metallic aluminum and its compounds is very extensive. Aluminum is widely used as a building material and for other uses where light weight and corrosion resistance are important. Aluminum oxide has industrial uses as an abrasive and catalyst. Medically, various soluble salts of aluminum have been used as astringents, styptics, and antiseptics. The insoluble salts are used as antacids and as antidiarrheal agents.
Aluminum hydroxide nebulization-induced redox imbalance and acute lung inflammation in mice
Published in Experimental Lung Research, 2020
Erika Tiemi Kozima, Ana Beatriz Farias de Souza, Thalles de Freitas Castro, Natália Alves de Matos, Nicole Elizabeth Philips, Guilherme de Paula Costa, André Talvani, Sílvia Dantas Cangussú, Frank Silva Bezerra
Examination of bronchoalveolar lavage revealed an increase in leukocytes, macrophages, neutrophils, and lymphocytes in animals exposed to aluminum hydroxide. Kim et al. observed an increase in the total cell, neutrophil, and lymphocyte count after exposure to aluminum.37 In addition, Kown et al. observed an increase in leukocytes, neutrophils, and lymphocytes after intratracheal instillation of aluminum oxide.42 Despite different aluminum compounds, methods of administration, and length of exposure, our results resemble those found in the literature, that exposure to aluminum promotes cell recruitment to the lung. Furthermore, we can infer from our study, that short-term ultrasonic nebulization with aluminum hydroxide induces a pulmonary inflammatory response in mice.
Effect of ceramic material type on the fracture load of inlay-retained and full-coverage fixed dental prostheses
Published in Biomaterial Investigations in Dentistry, 2020
Hamid Kermanshah, Fariba Motevasselian, Saeedeh Alavi Kakhaki, Mutlu Özcan
One of the methods of improving the translucency is to increase the yttria content to 5% or more. However, the resultant microstructure consists more of cubic phase which has lower mechanical properties [7,11]. There is little knowledge about the mechanical behavior and reliability of monolithic translucent zirconia used for IRFPDs. Moreover, zirconia is chemically stable [12] and lack of glassy matrix due to its high crystalline content. In fact, adhesion of the resin-based luting cement is essential for the longevity of IRFPDs but high crystalline content of zirconia makes it resistant to conventional conditioning methods used for silica-based ceramic (i.e. hydrofluoric acid (HF) etching and silanization) [12–14]. Different types of mechanical and chemical surface conditioning methods have been recommended to date. Air-abrasion with aluminum oxide particles (Al2O3) is the most commonly used mechanical treatment [14,15]. Among chemical conditioning methods, Kitayama et al. showed that fusing of a thin layer of silica based ceramic of zirconia ceramic followed by silanization can improve bond strength of resin cement [16]. Another approach leading to chemical interaction with zirconia is the use of functional monomers having an affinity for metal oxides which can be included in the resin cements and adhesives. Phosphate ester monomers, such as 10-methacryoloyloxydecyl dihydrogen phosphate (10-MDP) and phosphoric acid acrylate monomer are among these functional monomers [12,13].
Aluminum oxide nanoparticles mediated toxicity, loss of appendages in progeny of Drosophila melanogaster on chronic exposure
Published in Nanotoxicology, 2019
Avnika Singh Anand, Urmila Gahlot, Dipti N. Prasad, Ekta Kohli
Aluminum is the third most abundant metal, consisting about 8% of the earth crust, however, concerns have risen regarding aluminum induced toxicity since its effect as a neurotoxin was reported by Doelken (Doelken 1898; Wu et al. 2012). The fibrous form of aluminum oxide (Al2O3) is considered as toxin under the Environmental Protection Agency’s Toxics Release Inventory list. Aluminum nanoparticles (Al2O3 NPs) are at prime concern for its safer use by the Organization for Economic Co-Operation and Development (Park et al. 2016). In the current scenario, the safety of these particles is still debatable. Though Al2O3 NPs are considered less toxic in comparison to other nanoparticles there are several reports highlighting its toxic effect on biological models. Neurodevelopmental toxicity in the offspring of mice was caused on exposure to Al2O3 NPs (Zhang et al. 2018). Manufactured Al2O3 NPs might posses’ ability to induce cytotoxicity and can be carcinogenic and mutagenic because of the nano size and large surface area which increase their interaction with biological entities. NPs can cross the biological barriers and accumulate in various organs causing neurotoxicity, genotoxicity, immunotoxicity and developmental toxicity. Al2O3 NPs are known to stimulate ROS causing further deterioration of DNA, proteins, lipids and faster apoptosis (M'rad et al. 2018).